Lennox International Inc ML193UH Attic or Crawl Space For Intake Air in Feet, Number Of, 2” Pipe

TABLE 5

Maximum Allowable Intake or Exhaust Vent Length in Feet

NOTE - Size intake and exhaust pipe length separately. Values in table are for Intake OR Exhaust, not combined total. Both Intake and Exhaust must be same pipe size.

NOTE - Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.

Standard Termination at Elevation 0 - 10,000

Number Of			2” Pipe						2-1/2” Pipe						3” Pipe
90° Elbows			Model							Model					Model
Used
	045	070	090	110		135	045	070		090	110	135	045	070	090	110	135
1	81	66	44	24			115	100		68	43		137	137	118	118	114
2	76	61	39	19			110	95		63	38		132	132	113	113	109
3	71	56	34	14			105	90		58	33		127	127	108	108	104
4	66	51	29				100	85		53	28		122	122	103	103	99
5	61	46	24			n/a	95	80		48	23	n/a	117	117	98	98	94
6	56	41	19				90	75		43	18		112	112	93	93	89
7	51	36	14	n/a			85	70		38	13		107	107	88	88	84
8	46	31					80	65		33			102	102	83	83	79
9	41	26	n/a				75	60		28	n/a		97	97	78	78	74
10	36	21					70	55		23			92	92	73	73	69
					Concentric Termination Elevation 0 - 10,000
Number Of			2” Pipe						2-1/2” Pipe						3” Pipe
90° Elbows			Model							Model					Model
Usedl
	045	070	090	110		135	045	070		090	110	135	045	070	090	110	135
1	73	58	42	22			105	90		64	39		121	121	114	114	105
2	68	53	37	17			100	85		59	34		116	116	109	109	100
3	63	48	32	12			95	80		54	29		111	111	104	104	95
4	58	43	27				90	75		49	24		106	106	99	99	90
5	53	38	22			n/a	85	70		44	19	n/a	101	101	94	94	85
6	48	33	17				80	65		39	14		96	96	89	89	80
7	43	28	12	n/a			75	60		34			91	91	84	84	75
8	38	23					70	55		29	n/a		86	86	79	79	70
9	33	18	n/a				65	50		24			81	81	74	74	65
10	28	13					60	45		19			76	76	69	69	60

TABLE 6

Maximum Allowable Exhaust Vent Lengths With Furnace Installed in a Closet or Basement Using Ventilated

Attic or Crawl Space For Intake Air in Feet

NOTE - Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.

Standard Termination at Elevation 0 - 10,000

Number Of			2” Pipe					2-1/2” Pipe						3” Pipe
90° Elbows			Model						Model					Model
Used
	045	070	090	110	135	045	070		090	110	135	045	070	090	110	135
1	71	56	34	14		100	95		53	28		117	117	98	98	94
2	66	51	29	9		95	80		48	23		112	112	93	93	89
3	61	46	24	4		90	75		43	18		107	107	88	88	84
4	56	41	19			85	70		38	13		102	102	83	83	79
5	51	36	14		n/a	80	65		33	8	n/a	97	97	78	78	74
6	46	31	9	n/a		75	60		28	3		92	92	73	73	69
7	41	26	4			70	55		23			87	87	68	68	64
8	36	21	n/a			65	60		18	n/a		82	82	63	63	59
9	31	16				60	45		13			77	77	58	58	54

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